The present disclosure relates to an information processing apparatus, an information processing method, a program, and an imaging apparatus including an optical microscope, which process an image signal obtained by an image sensor to thereby correct distortion of an output image.
In the past, for example, a digital still camera including an image sensor such as a charge-coupled device (CCD) is widely used as an imaging device. When an image of an object is captured with such an imaging device, distortion may be caused in the captured image in some cases due to the shape of a lens included in the imaging device, or the like. To correct this distortion, various distortion correction techniques are used.
For example, in a calibration system disclosed in Japanese Patent Application Laid-open No. 2000-350239 (hereinafter, referred to as Patent Document 1), a distortion parameter used for correcting the distortion described above is estimated as follows. First, in the calibration system, a reference image constituted of patterns in which a geometrical shape is already defined is generated. Then, the reference image is projected onto a flat screen surface and captured with a camera. The reference image and the captured image of the reference image are subjected to image registration processing, with the result that a distortion parameter for distortion correction is estimated (see paragraph [0094] or the like of Patent Document 1).
Further, in Patent Document 1, based on a point nd on the captured image surface in which lens distortion is taken into consideration, a corresponding point nu on the captured image surface in which lens distortion is not taken into consideration is calculated. As described in paragraph [0084] of Patent Document 1, the point nu is calculated by an expression that is based on a distance from the center of distortion.